There is a conventional reforming furnace comprising a number of reaction pipes in the furnace and a number of burners on a furnace wall for uniform heating of the furnace, which is disclosed in, for example, Patent Literature 1. Such conventional reforming furnace is, however, disadvantageous in that it is much complex in structure, that complicated control is required for the uniform heating and that running cost is increased since only fuel gas, which is expensive, is usually used for the burners so as to attain the uniform burning.
In order to overcome these, there has been recently proposed a fluidized-bed employing reformer as disclosed in, for example, Patent Literature 2 or 3.
In Patent Literature 2, arranged side by side are a fluidized-bed heat decomposition gasification furnace for production of valuable gas or oil through feeding of solid or liquid raw material and a fluidized-bed combustion furnace for heating of circulating particles by combustion of carbon-containing residue and other flammable materials produced in the gasification furnace, the heated circulating particles in the combustion furnace being moved to the gasification furnace to heat the raw material.
In Patent Literature 3, raw material to be reformed which is a combination of hydrocarbon with steam is heated and reformed in a fluidized-bed catalyst reactor using catalyst particles, resultant reformed gas being used as fuel for a fuel cell. The catalyst particles separated from the reformed gas is guided to a heat exchanger where off gas from the fuel cell and free from hydrogen is burned to directly heat the catalyst particles, the heated catalyst particles being fed to the fluidized-bed catalyst reactor.    [Patent Literature 1] JP 2000-185905A    [Patent Literature 2] JP 2006-63290A    [Patent Literature 3] JP 2001-354405A